Lubricating preparation



Patented Jan. 4, i938 LUBRIOATING PREPARATION Hugh Francis Green, York, England No Drawing. Application August 5, 1935, Serial No. 34,842. In Great Britain December 5,

8 Claims.

This invention relates to improved lubricating preparations containing oils.

Y It is one object of the invention to provide an improved penetrating oil for creeping in between the leaves of leaf springs, easing rusted screwthreads and like purposes, and in particular to provide a composition more nearly of the consistency of gear oil than of an ordinary penetrating oil and yet having the property of creeping 10 between the leaves of springs and thereafter remaining between them and performing the functions of an eflicient lubricant.

It is believed however, that the composition hereinafter to be described will find many other applications and with obvious modifications, such as the selection of different types of lubricating oils, it is believed that the composition according to the invention will be suitable for a variety of purposes. Thus the invention may result in a lowering of the temperature at which oil solidifies, hence enabling the oil to be used in climates or for purposes, such as refrigeration, which involve lubrication at low temperatures, and in this latter connection for such purposes as power transmis- 05 sion liquids.

- A lubricating preparation according to the present invention comprises a lubricating oil and a neutralized hydroxy acid.

The neutralized hydroxy acid may be a salt or 30 an ester or in certain cases, a mixture of a salt and an ester of the same or different hydroxy acids. Where a salt is employed the ester of another hydroxy acid may be employed as a solubilizing agent in order to bring about compatibility between the oil and the hydroxy acid salt. Esters other than hydroxy acid esters, however, may be employed with a hydroxy acid salt to render the latter compatible with the oil, for example, amyl acetate and the glycerol esters of higher fatty 4i) acids such as palmitic, oleic or stearic acids.

According to onefeature of the invention, the neutralized hydroxy acid is an alkali salt of a hydroxy derivative of cholanic acid, Cad-14002. Examples of such acids are glyco cholic acid C24.Ha9.O4.NH.CHz.CO2H

and tauro cholic acid C24.H39.O4.NH.CH2.CH2.SOsH.

These two acids are constituents of the bile fluid and are known as bile acids. A pharmaceutical preparation from the bile of oxen which containsboth these acids is known as sodium tauro w glyco cholate.

According to another feature of the invention, a lubricant comprises a lubricating oil and a hydroxy acid ester such as a lactic acid ester. Where a lactic ester is employed, according to a preferred feature of the invention, it serves as a 5 solvent for a hydroxy derivative of cholanic acid such as sodium or potassium tauro glyco cholate. In this case, the lactic acid ester employed is preferably that of an aliphatic alcohol higher than that of butyl alcohol, 1. e. an aliphatic al- 10' preferably employed in proportions just sufficient to bring about compatibility between the lubricating oil and the bile salts.

The invention also includes the process for producing the improved lubricant which consists in adding a solution, in a solubilizing'agent, of a bile salt to a lubricating oil, for example, the addition of a solution of sodium tauro glyco cholate in amyl lactate to a mineral lubricating oil.

The invention .further includes the incorporation with the composition hereinbefore described of graphite preferably in colloidal condition.

In carrying out the invention, the hydroxy acid salt or ester, or both, may be added to a thick lubricating oil or it may be added as a constituent in a known penerating oil comprising a comparae tively heavy mineral oil to which kerosene and amyl acetate are added. In such known penetrating oils as hitherto prepared in order to obtain the desired fluidity and sufiicient penetrating power, the proportions of kerosene and amyl acetate added have been substantial, and it has been necessary to add graphite to the mixture to obtain suificient lubricating properties. In preparing such liquid in accordance with the present invention, the penetrating power of a, thick lubricating oil can be so increased by a very small proportion of the hydroxy acid that the amount of kerosene and graphite may be either substantially reduced or dispensed with altogether.

The following examples illustrate the nature of the invention though it will be appreciated that the proportions given may be varied in each case:-

Example 1 Example 2 Two drams of the same solution of bile salts as in Example 1 was added to one pint of thick gear oil sold under the name Mobiloil C. This results in a black thick oil which can be used for lubrication of leaf springs by painting it on the sides thereof when it will slowly creep in between the leaves and remain there for a considerable period.

Example 3 This is an example of the application of the invention to the preparation of a penetrating oil containing kerosene and amyl acetate. The proportions of the constituents-were as follows:

Lubricating oil sold as Rimers heavy grade H oil ounces 5 Kerosene do 4 Amyl acetate dram Concentrated solution of sodium tauro glyco cholate in alcohol dram.. 1 Graphite in the form sold as Rimers graphite suspension (running-in compound) dram -1 Instead of the alcohol neutral esters such as the glycerol esters or palmitic, oleic or stearic acidsmay be used as solvent for the tauro glyco cholate.

' What I claim as my invention and desire to secure by Letters Patent is: r

1. A lubricating preparation comprising a inbricating oil, a salt of a bile acid and a liquid lactate of an aliphatic alcohol having more than four carbon atoms.

2. A lubricating preparation comprising a lubricating oil and sodium tauro glyco cholate and a liquid lactate of an aliphatic alcohol having more than four carbon atoms, in suflicient quantityv to form a compatible solution with the lubricating oil.

3. A' lubricating preparation consisting of a lubricating oil and more than 0.1% of sodium tauro glyco cholate dissolved in suflicient amyl lactate to form a compatible solution with the lubricating oil.

4. A lubricating preparation comprising a lubricating oil and sodium tauro glyco cholate and suflicient amyl lactate to form a compatible solution with the lubricating oil.

5. A lubricating preparation comprising a mineral lubricating oil and sodium tauro glyco cholate and sufilcient amyl lactate to form a compatible solution with the mineral lubricating oil.

6. A process for preparing a lubricating preparation which comprises dissolving a salt of a bile acid in amyl lactate and adding the said solution to a lubricating oil.

'7. A process for preparing a lubricating preparation which comprises dissolving a salt of a bile acid in amyl lactate and adding the said solution to a mineral lubricating oil.

' 8. A process for preparing a lubricating preparation which comprises dissolving sodium tauro glyco cholate in suificient amyl lactate to form a compatible solution with a mineral lubricating oil and adding the said solutionto the lubricating oil.

HUGH FRANCIS GREEN. 

